package mytest;
import java.util.*;;

public class mymain {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		
		System.out.print(new Date());
		Properties p=System.getProperties();
		p.list(System.out);
		
		Runtime rt=Runtime.getRuntime();
		System.out.println("Total Memory="+rt.totalMemory()+"Free Memory="+rt.freeMemory());
	}

}

输出内容为：

Sun May 04 12:49:37 CST 2014-- listing properties --
java.runtime.name=Java(TM) SE Runtime Environment
sun.boot.library.path=C:\Program Files\Java\jre6\bin
java.vm.version=20.12-b01
java.vm.vendor=Sun Microsystems Inc.
java.vendor.url=http://java.sun.com/
path.separator=;
java.vm.name=Java HotSpot(TM) Client VM
file.encoding.pkg=sun.io
user.country=CN
sun.java.launcher=SUN_STANDARD
sun.os.patch.level=
java.vm.specification.name=Java Virtual Machine Specification
user.dir=C:\Users\dqq\workspace\mytest
java.runtime.version=1.6.0_37-b06
java.awt.graphicsenv=sun.awt.Win32GraphicsEnvironment
java.endorsed.dirs=C:\Program Files\Java\jre6\lib\endorsed
os.arch=x86
java.io.tmpdir=C:\Users\dqq\AppData\Local\Temp\
line.separator=


java.vm.specification.vendor=Sun Microsystems Inc.
user.variant=
os.name=Windows 7
sun.jnu.encoding=GBK
java.library.path=C:\Program Files\Java\jre6\bin;C:\Win...
java.specification.name=Java Platform API Specification
java.class.version=50.0
sun.management.compiler=HotSpot Client Compiler
os.version=6.1
user.home=C:\Users\dqq
user.timezone=Asia/Shanghai
java.awt.printerjob=sun.awt.windows.WPrinterJob
file.encoding=GBK
java.specification.version=1.6
user.name=dqq
java.class.path=C:\Users\dqq\workspace\mytest\bin
java.vm.specification.version=1.0
sun.arch.data.model=32
java.home=C:\Program Files\Java\jre6
sun.java.command=mytest.mymain
java.specification.vendor=Sun Microsystems Inc.
user.language=zh
awt.toolkit=sun.awt.windows.WToolkit
java.vm.info=mixed mode, sharing
java.version=1.6.0_37
java.ext.dirs=C:\Program Files\Java\jre6\lib\ext;C:...
sun.boot.class.path=C:\Program Files\Java\jre6\lib\resour...
java.vendor=Sun Microsystems Inc.
file.separator=\
java.vendor.url.bug=http://java.sun.com/cgi-bin/bugreport...
sun.cpu.endian=little
sun.io.unicode.encoding=UnicodeLittle
sun.desktop=windows
sun.cpu.isalist=pentium_pro+mmx pentium_pro pentium+m...
Total Memory=16252928Free Memory=15784080

这个是用来输出系统的一些配置。